This invention relates generally to a machine tool and more particularly it relates to a machine tool of the type having a driving spindle driven by an electromotor and a turret head portion for supporting a plurality of tool holders and for positioning a selected tool holder into alignment with the driving spindle, whereby the facing ends of the driving spindle and of the tool holder are provided with coupling members and further including feed mechanism for axial displacement of the driving spindle and the tool holder. From prior art an automatic machine tool of this type is known in the form of a turret drill in which the tool holders are made as drill spindles which include respectively a working spindle and driving gears assigned thereto. The driving spindle is driven by an alternating current motor and is directly coupled to each driver spindle. The rotary speed of the working tool is in each individual case determined by the transmission ratio of the gears in the drill spindle. As a consequence if a large range of rotary speeds is required there are necessary many drill spindles with corresponding transmission gears. However, the gears having a high transmission ratio are expensive and also there are problems as far as the size of the transmission unit and the torque transmission are concerned. To define the length and the speed of the feed of the tool each driver spindle is provided with its own signalling elements in the form of cams, fixed stops and switches, amount controllers and the like. As a rule, during the exchange of the working tool it is necessary to replace the whole driver spindle for another one so that the tool can be adjusted via the corresponding transmission gears to correct rotary speed and via each setting member to the correct feed. By means of the coupling between the driving spindle and the drill spindle, working tool is driven at the necessary rotational speed and a feed mechanism imparts the feeding movement to the coupling. As a consequence, a considerable axial pressure is to be taken up by the coupling elements. Respective drill spindles are transported into their position by mechanical means; they are seated in a turret in the form of a Maltese cross wheel which is driven by a separate motor and therefore only a steplike change of working position of respective drill spindles is possible. The disadvantage of such prior art arrangement of the machine tool is the fact that the positioning of respective working tools is difficult, the control of the working cycle is expensive, the power output--and the range of rotational speed is limited, adjustment time is large, the structure is heavy and due to the necessary transmission gears and motors very costly.